VoIP over Wi- Fi using Riverbed Simulation

Transcription

1 VoIP over Wi- Fi using Riverbed Simulation ENSC 427: Communication Networks Spring 2015 Team 10 Zhang Yuanjie Jiaqi Li Owen Au Webpage:

2 Road Map! Introduction (motivation of this project, wifi and riverbed details)! Voice over WiFi implemented in Riverbed! Discuss and analyze MOS factors! Performance of G.711 and G.729a! Summary

3 Introduction! WiFi- Wireless Fidelity! Local area wireless technology, support electronic devices to participate in computer networking! Riverbed Technology! Popular tool, Ericsson => benefit students! VoIP- delivery of voice communication over Internet Protocol! Important app, expected to carry more and more voice traffic over TCP/IP network (For example: Viber and Skype)! In this project, we simulate them in an office environment

4 VoIP over WiFi- Setup! 1 Application, 1 Profile, 1 Ethernet Server, 1 Router, 1000BaseX users at different distances

5 VoIP over WiFi MOS Values! MOS stands for mean opinion score! Obtains the user s view of the audio quality of the network! The score range is 1 to 5, 1 being the lowest quality! MOS > 4.3 (Very Good)! 3.5< MOS < 4.3 (Good)! 3 < MOS < 3.5 (Mediocre)! MOS < 2 (Bad)

6 Factors Affecting MOS! Delay! Jitter! Packet Loss

7 Delay results for different distances! Five distances: 250m,260m,265m,270m and 280m Distance= 265 m Distance= 280 m Distance= 260 m Distance= 250 m Distance= 270 m

8 Jitter results for different distances Jitter is variance of times between packets arriving Distance= 265 meters Distance= 280 meters Distance= 260 meters Distance= 250 meters Distance= 270 meters

9 Jitter- Queue size relationship! Jitter is directly related to how severe the traffic congestion which is determined by the queue size

10 Voice Packet Loss results for different distances! Traffic received is reduced as distance increases and more and more packets are dropped Distance= 250 meters Distance= 260 meters Distance= 265 meters Distance= 270 meters Distance= 280 meters

11 Voice Packet Loss results for different distances! Reason for Packet Loss? MOS Network Loss Rate! MOS Network Loss Rate = ratio of packets lost due to network factors to the total number of packets Distance= 280 meters Distance= 270 meters Distance= 265 meters Distance= 260 meters Distance= 250 meters

12 Packet loss due to buffer size As buffer size increases, lower packet loss and less congestion However too large of a buffer will introduce queuing delay fixed distance 260 meters Buffer size = 1 million bits Buffer size = bits Buffer size = bits Traffic Received Buffer size = 1 million bits Jitter Buffer size = 1 million bits Buffer size = bits Buffer size = bits MOS Value Buffer size = 1 million bits Delay

13 Packet loss due to Data Rate - - fixed distance 265 meters, user data rate = 24Mbps and change the router s data rate A high LAN router data rate will overrun the receiver buffer 54 Mbps 18, 36 Mbps Delay 18, 36 Mbps 54 Mbps Traffic Received 54 Mbps 18, 36 Mbps Packet loss rate 18, 36 Mbps 54 Mbps MOS Value

14 MOS values over different distances! A high MOS score requires low jitter, low delay, and minimal packet loss Distance= 250 meters Distance= 260 meters Distance= 265 meters Distance= 270 meters Distance= 280 meters

15 MOS values over different distances! MOS > 4.3 (Very Good) Range: meters! 3.5< MOS < 4.3 (Good) Range: meters! 3 < MOS < 3.5 (Mediocre) Range: meters! MOS < 2 (Bad) Range : more than 270 meters

16 WiFi MOS for G.711 and! Fixed distance = 200 meters G.729A! Our MOS Result is similar to PSQM testing result 4.03 for G. 729A and 4.45 for G.711 under ideal condition MOS= 4.45 G.711 MOS= 4.03 G.729A

17 G.711 vs. G.729A - G.711 seems to be more tolerable to jitter than G.729a MOS= 2.68 G.711 MOS= 2.54 G.729A

18 References! [1] Gupta, Ishu and Kaur, Perminder., Comparative Throughput of WiFi & Ethernet LANs using OPNET MODELER, International Journal of Computer Applications ( ), vol.8- No.6, 2010! [2] Izotope. What is Buffer Size and why is it important? Retrieved from support/kb/index.php/kb/article/503- What_is_Buffer_Size_and_why_is_it_important! [3] Ribadeneira, Alexander F., "An Analysis of the MOS under Conditions of Delay, Jitter and Packet Loss and an Analysis of the Impact of Introducing Piggybacking and Reed Solomon FEC for VOIP." Thesis, Georgia State University, Retrieved from [4] Voip.com (2008, May 09), G.729 versus G.711. Retrieved from g729- versus- g711.html! [5] Understanding Jitter in Packet Voice Networks (Cisco IOS Platforms) Retrieved from quality/ jitter- packet- voice.html! [6] Understanding Delay in Packet Voice Networks Retrieved from support/docs/voice/voice- quality/5125- delay- details.html! [7] UDP VS TCP for Voip Retrieved from voip/sip/udp- versus- tcp- for- voip

19 Questions??